radius + dhcp

[Alan DeKok]

marco perugini wrote:
> hi alan, first of all thanks for your feedback!
> now i'm going to explain better: i'm in WiMax context with freeradius
> 2.1.1 and i want to differentiate several clients to assign addresses
> according with realm;
> here's an example: i've client1 at realm1, client2 at realm1 and
> client3 at realm1 and there's also client4 at realm2. now i'd love that my
> dhcp assigns IPs from 10.x.x.x pool to the realm1's clients and IPs from
> 20.x.x.x pool to the realm2's client.

  Ah.  That's a very good use-case.

> so do you know if it's possible to do with classic dhcp server [dhcpd]?

  No.  It's pretty much impossible.

> or with freeradius's embedded dhcp server? or i'm guessing something
> impossible?

  It's possible, but it requires some code changes.  The server can send
and receive DHCP packets.  It can allocate IPs from SQL for RADIUS
queries.  But it can't yet allocate IPs from SQL for DHCP packets.

  What you *can* do is allocate IPs when the user logs in.  The NAS will
ignore the IP address in the Access-Accept, but the IP will still be in
the SQL database.  Then, when the DHCP packet comes in, SELECT the IP
based on the MAC address, and return it to the user.

  This should actually work in the current server...

  Alan DeKok.